A report being published by a team of hackers-turned-corporate warriors has estimated online advertising fraud is now netting $7.3bn per year for criminals who employ a team a worldwide network of “zombie” computers.

White Ops, an anti-botnet and -malware cyber-security firm, conducted a report, Bot Baseline: Fraud in Digital Advertising, with the Association of National Advertisers, looking at ad traffic from 49 advertisers over a two-month period.

It found the problem is not growing in proportion but certainly is in value.

“The exposure of all advertising has remained the same,” CEO Michael Tiffany tells Beet.TV in this video interview. “It was a $7.3bn impact. These botanist are being compromised all over the place.” The prior’ year’s study had found the problem to be worth $6.3bn.

Ad fraud is a problem that is often cited in ad buyers’ list of technology concerns. How does it work? Simply put, malware authors exploit weaknesses in consumers’ computers to inject malicious code that strings together thousands of machines in a network that can silently hit web pages, appearing to clock up payable ad views.

“Ad fraud is one of the best ways to make money if you command a robot army of regular consumers,” Tiffany explains. “Bots that visit a website look like real human visitors. Bots are a variety of malware built out of regular browsers.

“The reason we’re not winning the war is, for every advertiser that has reduced their bot exposure, some other parts of the net have just gotten that much dirtier. Cybercriminals that we’re up against are fantastic at making fake traffic look good.”

This video part of a series about the state of programmatic advertising sponsored by OpenX. Please find other videos from the series here.